Wireless communication system, server and mobile station therefor

• US 8,140,075 B2
• Filed: 10/26/2009
• Issued: 03/20/2012
• Est. Priority Date: 11/28/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Watanabe, Koji
• Primary Examiner(s): MILLER, BRANDON J
• Application Number:
  US12/588,719
• Publication Number:
  US 20100046475A1
• Time in Patent Office: 876 Days
• Field of Search: 455/552.1, 455/67.11, 455/434, 455/41.2, 455/466, 455/553.1, 455/432.1, 455/433, 455/435.1, 455436-443, 370/338, 370/331, 370/349, 370/328, 370/334
• US Class Current: 455/436
• CPC Class Codes: H04W 36/0019 adapted for mobile IP [MIP]
• CPC Class Codes: H04W 36/144 over a different radio air interface technology
• CPC Class Codes: H04W 40/36 due to handover
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 60/04 using triggered events
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

This invention provides a wireless communication system wherein a network to which a mobile station should be handed over can be selected, using parametric data collected from network components other than the mobile station. Time taken for a handover between different types of network systems is reduced. The wireless communication system of the present invention comprises a mobile station equipped with multiple wireless interfaces, a server connected to a fixed network, and multiple access points. The mobile station determines available wireless interfaces and sends notification of the available interfaces'"'"' identifiers to the server. The server collects managerial data from network components and selects a wireless interface, based on the notification from the mobile station and the managerial data. The mobile station registers its locations in visiting networks corresponding to multiple available wireless interfaces with the server. The server retains the registrations of mobile station locations for the above wireless interfaces.

Claims

1. A wireless communication system, comprising:

a mobile station which includes a first wireless interface corresponding to a first wireless communication protocol and a second wireless interface corresponding to a second wireless communication protocol;

a server connected to a network;

a first access point coupled to the network and to report according to the first wireless communication protocol; and

a second access point coupled to the network and to report according to the second wireless communication protocol;

wherein the first access point reports, to the server, a first communication information of a first wireless communication condition, wherein the first wireless communication condition comprises a radio condition between the first access point and the mobile station which has been accommodated by the first access point,

the mobile station sends, to the server, a handover request to change communication path of the mobile station from the second access point to the first access point,

the server determines whether to change communication path of the mobile station from the second access point to the first access point on the basis of the first communication information, and

if it is determined to change the communication path from the second access point to the first access point, the server controls packet transmission path routing related to the mobile station for handover of the mobile station.

2. A wireless communication system according to claim 1,

wherein:

the second access point reports, to the server, a second communication information of a second wireless communication condition related to the second wireless communication protocol, wherein the second wireless communication condition comprises a radio condition between the second access point and the mobile station which has been accommodated by the second access point, and

the server compares between the first communication information and the second communication information to determine whether to change communication path and sends handover recommendation message to the mobile station on the result of the comparison.

3. A wireless communication system according to claim 2,

wherein the first communication information includes at least one of packet discard ratios, packet error counts, a number of packets received at the access points, and an amount of data received per unit.

4. A wireless communication system according to claim 2,

wherein the first communication information is related to a communication condition of communication between the first access point and a plurality of mobile stations which are accommodated by the first access point.

5. A wireless communication system according to claim 2,

wherein the second communication information is related to communication condition between the second access point and a plurality of mobile stations which are accommodated by the second access point.

6. A wireless communication system according to claim 2,

wherein the mobile station receives the handover recommendation message from the server, and determines whether to change from the second wireless network interface to the first wireless network interface on the basis of the handover recommendation message.

7. A wireless communication method in a network system including a first access point to report according to a first wireless communication protocol, a second access point to report according to a second wireless communication protocol and a server coupled to the first access point and the second access point, the method comprising the steps of:

providing, a mobile station, a first wireless communication network according to the first wireless communication protocol and a second wireless communication network according to the second wireless communication protocol;

collecting, by the server, a first information related to a condition of the first wireless communication network and a second information related to a condition of the second wireless communication network; and

sending, by the server, to the mobile which is accommodated by either the first access point or the second access point, a handover recommendation request to recommend handover between the first wireless communication network and the second wireless communication network on the basis of the first information and the second information.

8. A wireless communication method according to claim 7, further comprising the step of:

sending, a handover request, by the mobile station, to either the first access point or the second access point, wherein the handover request is for handing over the mobile station between the first access point and the second access point.

9. A wireless communication method according to claim 7,

wherein if a condition of a wireless network provided by an access point which has not accommodated the mobile station is better than that of a wireless network provided by an access point which has accommodated the mobile station, then the method further comprises the step of determining, by the server, to send a handover recommendation message to the mobile station.

10. A mobile station comprising:

a first wireless network interface operably associated with a first wireless network, the first wireless network having a first access point coupled to a server via a network;

a second wireless network interface operably associated with a second wireless network, the second wireless network having a second access point coupled to the server via the network;

a control unit which is coupled to the first wireless network interface and the second wireless network interface, and which communicates via the first wireless network interface to the first access point which has accommodated the mobile station;

wherein the control unit receives a handover recommendation message from the server via the first wireless network interface,

with response to the handover recommendation message, sending a handover request message via the first wireless network interface to the first access point, and,

after sending the handover request message, communicates to the second access point which accommodates the mobile station via the second wireless network interface.

11. A mobile station according to claim 10,

wherein the handover recommendation message is created by the server on the basis of result of comparison between a first wireless network condition and a second wireless network condition.